An evangelical Christian who is one of the world’s top scientists is trying to save the life of Christopher Hitchens, the cancer-stricken writer who told him at their first meeting that God does not exist.

Francis Collins, who led the projec to map human genes, contacted the atheist when he was diagnosed with terminal cancer last year.

Hitchens was sent to Washington University School of Medicine in St. Louis, where scientists sequenced the 6 billion letters of his DNA. Using computers in a process that takes several weeks, they also sequenced the 6 billion letters in his his tumours, Then they looked at the two sets for differences.

‘Over these last few months, we have not talked directly about faith,’ Collins said, ‘But I would like to think that Christopher’s sharp intellect has challenged my own defence of the rationality of faith to be more consistent and compelling.’